Why Study the Baboons on Foot?

The Okavango Delta is a place of beauty, adventure, and danger — home to lions, leopards, hyenas, hippos, and more. In early 1977, Steve, Barbara, and I arrived there as students to begin a long-term study of chacma baboons (Papio ursinus), and we fully expected to observe them from the relative safety of a vehicle.

Our professor at U.C. Davis, William J. Hamilton III (“Bill”), had worked in the Okavango before, at a site about fifteen miles from our new one. Knowing the dangers, he and his previous students had conducted all their observations from a vehicle, and Bill assumed we would do the same.

So I was tasked with buying a used Land Rover in Namibia. I drove it across the Kalahari Desert to Maun, the frontier town at the edge of the Delta. From there, we loaded the Rover and our supplies onto a barge and spent a full day chugging up the Thamalakane and Boro rivers to the new research site, just inside the Moremi Wildlife Reserve and near the center of the Okavango.

Bill coined the expression “evolutionarily relevant context” to describe an ideal field site, one minimally affected by humans and as close as possible to the habitat and conditions in which the study species evolved. For this reason, he was especially drawn to the Okavango. He even insisted that we study a baboon troop whose range did not overlap with our camp, reasoning that predators such as leopards and lions might avoid the camp area, preventing us from observing predation at natural levels. (We would eventually break this rule.)

We consulted our neighbors, P. J. and Joyce Bestelink, who had recently established the Xaxaba tourist camp¹ just two miles down the Boro river. They suggested we search for baboons on White Island — the largest island nearby — which, they assured us, supported abundant wildlife, including its fair share of predators. The floodwaters were high at the time, but P. J. detailed a circuitous route that had only one sketchy water crossing (~3 feet deep).

With a marked aerial photograph in hand, we set off for White Island. Almost immediately, we encountered our first real problem: tsetse flies. They swarmed the vehicle, slipping through every crack and seam. The person in the passenger seat became the designated “fly-swatter” instead of “shotgun.” Their bites were painful and relentless. We learned that if we drove faster than 25 miles per hour, we could outrun them — but the sandy, swampy terrain rarely allowed it.

On one of our first drives to White Island, we got hopelessly stuck in the mud while emerging from a deep water crossing next to a termite mound. We had discovered first hand that the soil around termite mounds turns especially treacherous when wet. We had to walk two miles back to camp and return the next day with some planks to help dig out the Rover. But something curious happened on the walk back: we noticed that the tsetse flies were not as thick. Hmm.

The vehicle finally freed, we reached the sandy middle of White Island and located a baboon troop. At first they were skittish around the vehicle, and even more so if we stepped outside. So for the next week or two we drove out to White Island almost every day and watched the baboons from the safety of the vehicle.

More problems arose with the vehicle. We were getting regular flat tires, punctures from acacia thorns that in some cases were two inches long. We learned to avoid driving under acacia trees, although we still got some flat tires. We had no choice but to perform most of the vehicle repairs ourselves, such as disassembling and cleaning the starter motor after it got wet from multiple crossings though deep water.

Steve and I had previously worked at Gombe in East Africa, studying chimpanzees in a setting without roads or vehicles. We were accustomed to observing animals on foot, though Gombe posed fewer dangers than the Okavango. It soon became clear that following the baboons by vehicle was untenable. We were already beginning to recognize individuals, but tracking a specific baboon through dense brush in the Rover was nearly impossible — especially if we each wanted to observe different individuals, as we had at Gombe.

We eventually abandoned the idea of following the baboons by vehicle. Instead, we would drive out early each morning to their sleeping trees (always the same spot) then follow them on foot throughout the day before driving the four miles back to camp. Surprisingly, the tsetse flies were far more tolerable on foot than in the vehicle, and the number of bites we received each day dropped dramatically.

At first, the baboons fled from us. But we borrowed a strategy pioneered by Jane Goodall. She had gained the trust of a chimpanzee she named David Greybeard — an individual who, for whatever reason, did not fear her.

We found our own David Greybeard, in fact, two of them: an older male we named Striker and a female named Rena who showed little concern about our presence. By staying close to them, like Jane had with David Greybeard, we gradually gained the tolerance and the trust of the entire troop.

Following the baboons on foot was liberating. That is, until a few weeks later when three lionesses ambushed the troop (unsucessfully). It was the first time Steve and I had ever seen lions. They stopped about 50 yards away, and we figured that our best option was to climb a tree. We scrambled into the crotch of a scrawny little tree, barely six feet off the ground. The lions looked at us — surely wondering what we were doing — then turned and walked away. We would encounter these lions many more times, including while on foot with the baboons, but they rarely showed any aggression toward us.

A few months later, Bill came to visit the camp. He was surprised to learn that we were following the baboons on foot, but we made a strong case, and he came to see that our observations were far better than what we could achieve from a vehicle. The reduced tsetse fly exposure helped make the argument—as did the savings in fuel, maintenance, and vehicle wear and tear.

Early on, we also received a visit from Lloyd Wilmot, the original owner of Xaxaba Camp and a legendary bush guide known throughout Botswana. One morning, Lloyd neatly explained his philosophy of life. He cleared a patch of sand and, with a finger, drew a simple graph. I can’t recall the exact axes — something like “risk” versus “probability of survival.” Across it, he drew a line and told us that on one side was where life was lived to its fullest. Lloyd truly embodied that philosophy (for example, see the photo below, right).

In the years that followed, as we walked with the baboons, we students found ourselves crossing that line more than once — usually not by choice. Those moments were as exhilarating as they were unsettling. Thankfully, every one of us lived to tell our stories.

---

1. Xaxaba is now a high-end luxury tourist camp called Eagle Island Lodge. P. J. would go on to found and operate Okavango Horse Safaris from 1986 until 2025. ↩︎